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Interpretation Response #02-0106 ([Baker Hughes] [Shelley Espinoza])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Baker Hughes

Individual Name: Shelley Espinoza

Location State: TX Country: US

View the Interpretation Document

Response text:

May 17, 2002

Ms. Shelley Espinoza                 Reference No. 02-0106
Sr. HSE Advisor
Baker Hughes
2001 Rankin Road
Houston, Texas 77073

Dear Ms. Espinoza,

This is in response to your letter dated April 2, 2002, requesting clarification of a transport vehicle and an overpack under the Hazardous Materials Regulations (HMR; 49 CFR Parts 100-185) as applied to a particular enclosure. Specifically you state that the enclosure is a box that is welded, bolted or otherwise permanently or semi-permanently attached to the bed of an open bed vehicle and is not part of the original vehicle construction.  The box is used to protect and consolidate hazardous material packages from one consignor.  You also convey your understanding that the box would be considered an overpack if it is less than 64 cubic feet.

As defined in § 171.8, a transport vehicle is a cargo-carrying vehicle such as an automobile, tractor, truck, etc. used for the transportation of cargo by any mode.  An overpack is an enclosure used by a single consignor to provide protection or convenience in the handling of a package or to consolidate two or more packages.  An overpack does not include a transport vehicle.  An example of an ovepack is one or more packages placed in a protective outer packaging such as a box or crate.  An overpack must meet the definition in § 171.8 and is not determined by its cubic feet limitation.  A reference to a limitation of 64 cubic feet is found in § 171.8 under the definition of a freight container.  However, it does not apply to a transport vehicle or an overpack.

It is our opinion that the described enclosure mounted on the vehicle is a modification to the transport vehicle.  It is now a permanent or semi-permanent attachment of the vehicle.  The vehicle and the affixed enclosure is considered a transport vehicle.

I hope this information is helpful.  If we can be of further assistance, do not hesitate to contact us.


Delmer F. Billings
Chief, Standards Development
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
171.8 Definitions and abbreviations